Dinoflagellate Endosymbiont of the Soft Coral Stichodactyla haddoni Saville-Kent Collected from the Coast of Hormuz Island,Strait of Hormuz

Russian Journal of Marine Biology - An endosymbiotic dinoflagellate isolated from the soft coral Stichodactyla haddoni from the coast of Hormuz Island, Strait of Hormuz, Persian Gulf, has been...     

Effect of water stress on growth, osmotic adjustment, cell wall elasticity and water-use efficiency in Spartina alterniflora

In the northern spring–summer season of 2004–2005, vegetative propagated plants of Spartina alterniflora were grown under control and water stress conditions on the Mediterranean sea shore of the south-east of Tunis. Control plants were irrigated every week and water stress plants were irrigated until the soil achieved 50% (mild stress) and 25% (severe stress) field capacity (FC). Dry and fresh weight at the whole plant level (g plant⁻¹), shoot to root ratio on dry and fresh weight, photosynthesis (A), transpiration rate (E), instantaneous water-use efficiency (WUE_i), leaf water potential (Ψw), leaf water content (WC), osmotic potential at full turgor (Ψs¹⁰⁰), osmotic potential at turgor loss point (Ψs⁰), osmotic adjustment (OA), proline, sugars, inorganic compounds and cell wall elasticity (CWE) were evaluated during a period of 6 days period between 82 and 90 days after the beginning of treatment (DAT). Plants grown under severe and mild-water stress showed lower Ψw than in control plants with values that averaged −3.1, −1.6 and −0.9 MPa, respectively. S. alterniflora plants submitted to mild-water stress exhibited OA and a decrease in CWE. However, under severe water stress the OA was not observed and CWE also decreased, but it was higher than in the mild-water stress. OA was mainly explained by the accumulation of nitrates, sugars and at a lesser degree, proline. S. alterniflora had a strong decline of the dry and fresh weight of the whole plant associated to a marked decrease of photosynthesis (A) and transpiration (E) in response to water stress, although WUE_i was increased. These results suggest that OA and WUE_i can be important components of the water stress adaptation mechanism in this species, but they are not sufficient enough to contribute to resistance to water stress.     

Effect of Drying Process and Wall Material on the Properties of Encapsulated Cardamom Oil

The retention and shelf stability of cardamom oil entrapped in freeze- and spray-dried microcapsules coated with skim milk powder and modified starch was investigated. It was found that the retention of flavor in freeze-dried matrices was low and independent from the composition of wall material, whereas for the spray-dried microcapsules, it was much higher and markedly dependent on the type and percentage of coating material. It was also shown that the particle size of spray-dried powder greatly contributed to the flavor retention and surface oil content of microcapsules. Additionally, microscopic observation of powder particles revealed that the type of wall material and drying method distinctly influenced the morphological characteristics of powders which presumably caused a difference in their capability of cardamom oil retention.     

Hotspots of (sub)alpine plants in the Irano-Anatolian global biodiversity hotspot are insufficiently protected

Aim

The mountainous regions in SW Asia harbour a high number of endemic species, many of which are restricted to the high-elevation zone. The (sub)alpine habitats of the region are under particular threat due to global change, but their biodiversity hotspots and conservation status have not been investigated so far.

Location

Subalpine-alpine habitats of SW Asia.

Methods

Distribution data of all (sub)alpine vascular plant species of the region were compiled, resulting in 19,680 localities from 1672 (sub)alpine species, the majority of them being restricted to the region (76%). Six quantitative indices of species diversity were used on the basis of 0.5° × 0.5° grid cells to identify (sub)alpine hotspots. Hotspots whose surface area in the (sub)alpine zone was covered by nature reserves maximally by 10% were defined as conservation gaps.

Results

A high proportion (80%) of the endemic species of the study area is range-restricted and narrowly distributed. The results of all six indices were highly correlated. Using the top 5%, 10% and 20% richest cells supported by any index, 32, 53 and 98 cells, respectively, were identified as Hotspots. Almost 60% of these Hotspots at all three levels were identified as unprotected (i.e. constituted Conservation Gaps). Generally, only 22%, 18% and 16%, respectively, of the alpine surface area of the identified Hotspots were covered by nature reserves for the top 5%, 10% and 20% richest cells, respectively.

Main conclusions

Although the rate of protection in (sub)alpine Hotspots exceeds that of the entire region it is still insufficient, because these Hotspots are much richer in endemic and in range-restricted species, but at the same time are under high pressure of global change. Therefore, the establishment of new nature reserves with high conservation efficiency in (sub)alpine habitats with a particular focus on the identified Hotspots is strongly recommended.     

Fractionation of Protein Hydrolysates of Fish Waste Using Membrane Ultrafiltration: Investigation of Antibacterial and Antioxidant Activities

Probiotics and Antimicrobial Proteins - In this study, yellowfin tuna (Thunnus albacores) viscera were hydrolyzed with protamex to obtain hydrolysate that is separated by a membrane ultrafiltration...     

iPSC modeling of stage-specific leukemogenesis reveals BAALC as a key oncogene in severe congenital neutropenia

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Inhibition of the SUV4-20 H1 histone methyltransferase increases frataxin expression in Friedreich's ataxia patient cells

The molecular mechanisms of reduced frataxin (FXN) expression in Friedreich''s ataxia (FRDA) are linked to epigenetic modification of the FXN locus caused by the disease-associated GAA expansion. Here, we identify that SUV4-20 histone methyltransferases, specifically SUV4-20 H1, play an important role in the regulation of FXN expression and represent a novel therapeutic target. Using a human FXN–GAA–Luciferase repeat expansion genomic DNA reporter model of FRDA, we screened the Structural Genomics Consortium epigenetic probe collection. We found that pharmacological inhibition of the SUV4-20 methyltransferases by the tool compound A-196 increased the expression of FXN by ∼1.5-fold in the reporter cell line. In several FRDA cell lines and patient-derived primary peripheral blood mononuclear cells, A-196 increased FXN expression by up to 2-fold, an effect not seen in WT cells. SUV4-20 inhibition was accompanied by a reduction in H4K20me2 and H4K20me3 and an increase in H4K20me1, but only modest (1.4–7.8%) perturbation in genome-wide expression was observed. Finally, based on the structural activity relationship and crystal structure of A-196, novel small molecule A-196 analogs were synthesized and shown to give a 20-fold increase in potency for increasing FXN expression. Overall, our results suggest that histone methylation is important in the regulation of FXN expression and highlight SUV4-20 H1 as a potential novel therapeutic target for FRDA.